下列关于Levey-Jennings质控图的说法错误的是（）。<br>A:y轴为浓度单位<br>B:χ轴为日期或分析批<br>C:画出的水平线相当于<img src="/Image1/49/49ae9c351be22d90d42767f0c6d5d623.jpg" />、<img src="/Image1/49/49ae9c351be22d90d42767f0c6d5d623.jpg" />±1s、<img src="/Image1/49/49ae9c351be22d90d42767f0c6d5d623.jpg" />±2s、<img src="/Image1/49/49ae9c351be22d90d42767f0c6d5d623.jpg" />±3s<br>D:只能用一种颜色区分质控限<br>E:一般<img src="/Image1/49/49ae9c351be22d90d42767f0c6d5d623.jpg" />±2s为警告限，<img src="/Image1/49/49ae9c351be22d90d42767f0c6d5d623.jpg" />±3s为失控限